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What size injectors?

  • Thread starter Thread starter 1990saleen
  • Start date Start date Jan 29, 2004
1

1990saleen

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#1
  • Jan 29, 2004
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I have a stock bottom end 302, with GT 40P heads, E-303 cam, GT 40 intake, 70mm throttle body, 1.6 rocker arms, and headers. Can I stay with the 19# injectors or do I need 24's. Also, what sort of horsepower #'s am I looking at?
 

65ShelbyClone

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#2
  • Jan 29, 2004
  • #2
You can keep the 19s, but you'll have to raise the pressure quite a bit. With 24s and a matching MAF you can run stock pressure (roughly). Either way a higher volume fuel pump is a good idea too.

I'd say you have a 275rwhp+/- capable engine. Whether or not it achieves that is another matter, but you have the parts for it.
 

onebdlx

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#3
  • Jan 29, 2004
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Like 65 stated, I would go with the 24's
 
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1990saleen

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http://www.summitracing.com/landing...{40BD2E7F-A55C-429C-A46A-11656EBE1B24}&Type=5

Just found the answer!!! Its 19#. Anyone else needing this information here is a great web site.
 
9

9 Deuce GT

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Dec 10, 2003
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#5
  • Jan 30, 2004
  • #5
I have a similar combo. 24# will work fine.
 

mike keirstead

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The 19s will work with increased fuel pressure. The 19s are good till 340 FWHP or so. That is when they are 100% duty cycle. 24s would do the job EASIER. If you have the money get the 24s so you will have room to grow. If you keep the 19s you will need and adjustable fuel regulator so you can crank up the pressure. Even if you get the 24s an adjustable regulator would be a good idea to have the car tuned VERY GOOD on a dyno with a wide band o2 sensor.
 
8

87gtconv

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#7
  • Jan 30, 2004
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Even Ford went with 24# injectors on the Cobra model and I dont think that made 300 honest hp on the rollers!!
 

5spd GT

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#8
  • Jan 30, 2004
  • #8
87gtconv said:
Even Ford went with 24# injectors on the Cobra model and I dont think that made 300 honest hp on the rollers!!
Click to expand...

True...Its better to go with 24's (just to make it easier) but depending on how money is you can stick with 19's and get an AFPR to up the pressure a bit.
 

mike keirstead

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87gtconv said:
Even Ford went with 24# injectors on the Cobra model and I dont think that made 300 honest hp on the rollers!!
Click to expand...


19s will do the trick but 24s will do it EASIER.
 

Mustang88LXKid

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#10
  • Jan 30, 2004
  • #10
Use the 24lbs, I have them for a similar combo as you do. Work great.
 

65ShelbyClone

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Jan 30, 2004
#11
  • Jan 30, 2004
  • #11
mike keirstead said:
The 19s will work with increased fuel pressure. The 19s are good till 340 FWHP or so. That is when they are 100% duty cycle. 24s would do the job EASIER. If you have the money get the 24s so you will have room to grow. If you keep the 19s you will need and adjustable fuel regulator so you can crank up the pressure. Even if you get the 24s an adjustable regulator would be a good idea to have the car tuned VERY GOOD on a dyno with a wide band o2 sensor.
Click to expand...

19s may be able to support 340hp, but 100% duty cycle is not good. 80% is about the max you want to go on any injector so you still have fuel control. 340hp - 20% = 272fwhp. Even if you dont have 80%+ duty cycle, you cant run too much fuel pressure either or the injectors can go static(lock open for anyone unfamiliar) and once again you lose fuel control. That would mean that 1990saleen is at or near the limit already.
 

5.0Droptop

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#12
  • Jan 30, 2004
  • #12
I wouldnt run 19# injs past 55 psi........But thats me
 

mike keirstead

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#13
  • Jan 30, 2004
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65ShelbyClone said:
19s may be able to support 340hp, but 100% duty cycle is not good. 80% is about the max you want to go on any injector so you still have fuel control. 340hp - 20% = 272fwhp. Even if you dont have 80%+ duty cycle, you cant run too much fuel pressure either or the injectors can go static(lock open for anyone unfamiliar) and once again you lose fuel control. That would mean that 1990saleen is at or near the limit already.
Click to expand...


I know alot of guys that are using 19s with his combo. If he has the money he should get the 24s. But the 19s will be OK if he dosnt have the money.

There is guys on corral running spray with 19s and they have 350 RWHP. They say no problems. 24s would be better but 19s will work.
 
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